Natural Diversity and Mutant Analysis of Regulators of Plant Immunity for Rational Design of Immunity Proteins as Decoys

University Of California-Berkeley, Berkeley CA

Investigators

Abstract

Plant pathogens cause tremendous crop losses worldwide and evolve quickly to overwhelm existing host immunity. Many pathogens deliver effector proteins into their hosts to promote virulence of the pathogen. Over evolutionary time, the plant can evolve to recognize specific effector proteins from the pathogen. The PI's research group has identified a plant protein (a "decoy") that acts as a "mousetrap" for a pathogen effector protein, and enables the plant to mount a strong immune response. This work will determine the genetic parameters necessary for pathogen recognition in the host, in order to help design better decoys and protect crops from infection. This project includes substantial outreach to a local two-year college that serves a diverse student body, including underrepresented groups (37% Hispanic, 24% African American, 19% Asian, 1% Hawaiian) and underprivileged students (68% receive financial aid), in order to expose students to cutting-edge research and broader educational opportunities. Dissection of the molecular determinants underlying host immunity will provide a rigorous toolkit to combat the significant problem posed by plant pathogens. HopZ1a, a Pseudomonas syringae type III secreted effector protein, is recognized indirectly through ZAR1, a nucleotide-binding site leucine-rich repeat containing receptor protein, when HopZ1a acetylates the ZED1 pseudokinase. ZED1 appears to be a decoy that has evolved to trap the T3SE into recognition, as it is not a functional kinase and does not have a role in basal immunity. This work will examine ZAR1 and ZED1 natural and mutant diversity in order to develop constraints for rational design of a pathogen decoy. The PI will collaborate with a local two-year college that primarily serves underprivileged students and underrepresented groups, and will host several students each summer to learn new scientific techniques. The lab will design a module on plant immunity that will be taught in the college. This will provide teaching opportunities for students and post-docs, and increase the participation of underrepresented groups in science. Together these efforts will encourage underrepresented students to pursue and excel at multi-disciplinary scientific research, provide outreach opportunities for graduate students and post-docs, and make progress on significant scientific and agricultural problems.